Noah Kraft,Richard Fritz Lanman,Dan Wiggins,Jonathan Oswaks,Nils Jacob Palmborg
申请号：
US14601901
公开号：
US09131308B2
申请日:
2015.01.21
申请国别(地区):
US
年份:
2015
代理人:
摘要：
There is disclosed a passive acoustical filter including two or more filter elements coupled between an ambient and a listeners ear, each of the filter elements selected from the group consisting of a low pass filter element, a high pass filter element, a band reject filter element, and a band pass filter element.
